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{{DISPLAYTITLE:microQ — Process Workflows}}
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     QNANO / microQ — Fabrication Process Workflows
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'''Step-by-step fabrication guides''' for common device types — showing which UQ facility and instrument you need at each stage.

{| class="wikitable" style="margin-bottom:1.2em;"
! colspan="2" style="background:#1a1814; color:#fff; font-family:monospace;" | Facility Key
|-
| style="width:140px;" | '''CMM''' || Hawken Building
|-
| '''ANFF-Q''' || AIBN Building
|-
| '''SMP''' || Parnell Building
|-
| '''Long Pocket''' || Long Pocket Campus
|-
| '''COPE''' || SCMB Building
|}

__TOC__

----

== Bio-MEMS — Microfluidics & Bio-Optomechanics ==

Workflows for microfluidic lab-on-chip devices, PDMS channel fabrication, and optomechanical biosensors. Sub-workflows range from pure soft lithography (no EBL) through to high-resolution EBL-defined features combined with deep silicon etching.

=== Workflow 1 — PDMS Soft Lithography Microfluidic Chip ===

''The standard route for PDMS lab-on-chip devices. SU-8 master fabricated at Long Pocket or ANFF-Q, PDMS cast and bonded to glass. No EBL needed for features >5 µm.''

'''Facility route:''' Long Pocket → Long Pocket → Long Pocket → ANFF-Q → Long Pocket

==== Steps ====

# '''Design and Print Photomask'''<br>Design channel layout in CAD (AutoCAD, KLayout, or L-Edit). Print a chrome or film photomask, or use ANFF-Q's direct-write laser system to pattern the master mould directly — skipping the physical mask entirely for prototyping.
# '''SU-8 Master Fabrication'''<br>Spin SU-8 negative photoresist onto a silicon wafer. UV-expose through photomask. Post-exposure bake, then develop to reveal raised SU-8 channel features. Feature height is set by SU-8 thickness (spin speed).
# '''PDMS Moulding and Curing'''<br>Silanise master mould to prevent PDMS adhesion. Mix PDMS base:crosslinker (10:1), degas, pour over master, and cure at 65–80 °C. Peel off cured PDMS slab and punch inlet/outlet holes.
# '''O₂ Plasma Activation and Bonding'''<br>Activate PDMS and glass substrate surfaces with O₂ plasma. Immediately bring surfaces into contact to form irreversible covalent bonds. Bake at 80 °C for 30 min to complete bonding.
# '''Device Testing and Characterisation'''<br>Verify channel dimensions by confocal or optical microscopy. Test fluidic connections and flow profiles. For integrated electrodes or sensors, use ANFF-Q probe station for electrical characterisation.

{{Hint|For features >10 µm, Long Pocket is the most straightforward route. For features 1–10 µm or if you need alignment to existing structures, use ANFF-Q's photolithography suite which has better alignment capability.}}

==== Summary ====

{| class="wikitable"
|-
! Parameter !! Detail
|-
| '''Typical timeline''' || Master fabrication: 1 day · PDMS casting + curing: 4–12 hrs · Bonding + test: 2–4 hrs · '''Total: 2–3 days'''
|-
| '''Primary facility''' || Long Pocket cleanroom
|-
| '''Supporting facility''' || ANFF-Q (AIBN) — plasma / alternative
|-
| '''Key instruments''' || SU-8 stream (ANFF-Q) · Microfluidics platform (ANFF-Q) · O₂ plasma cleaner (ANFF-Q) · Soft lithography tools (ANFF-Q)
|}

----

=== Workflow 2 — Thermoplastic Microfluidics via Hot Embossing ===

''Hot embossing of thermoplastic substrates (COC, PMMA, PC) using a silicon or SU-8 master. Better for mass replication than PDMS. Requires ANFF-Q hot embosser.''

'''Facility route:''' ANFF-Q → ANFF-Q → ANFF-Q → ANFF-Q

==== Steps ====

# '''Si or SU-8 Master Fabrication'''<br>Fabricate a rigid master mould from silicon (via DRIE) or SU-8. Silicon masters give higher feature fidelity and longer lifetime. DRIE provides high-aspect-ratio features with vertical sidewalls.
# '''Hot Embossing'''<br>Load thermoplastic substrate and master into the hot embosser. Heat above glass transition temperature (Tg), apply pressure to imprint features, cool under pressure, then demould. ANFF-Q hot embosser handles COC, PMMA, and PC.
# '''Drilling / Punching Inlets'''<br>Drill or punch fluidic access holes in the embossed substrate using a micro-drill press or laser micromachining system.
# '''Thermal / Solvent Bonding'''<br>Bond embossed substrate to lid layer by thermal bonding (just below Tg) or solvent-assisted bonding. Seal channels and verify under microscope.

==== Summary ====

{| class="wikitable"
|-
! Parameter !! Detail
|-
| '''Primary facility''' || ANFF-Q (AIBN)
|-
| '''Key instruments''' || Hot embosser (ANFF-Q) · DRIE (ANFF-Q) · Oxford Lasers micromachining
|}

----

=== Workflow 3 — EBL-Defined Nanoscale Features in Microfluidic Devices ===

''For sub-micron features (nanochannels, nanofilters, plasmonic sensors in microfluidics). Combines EBL at CMM with DRIE or RIE at ANFF-Q, then PDMS integration at Long Pocket.''

'''Facility route:''' CMM → CMM → ANFF-Q → CMM → Long Pocket

==== Steps ====

# '''Resist Coat and EBL Exposure'''<br>Plasma clean substrate, spin coat ZEP520A or PMMA, bake. Expose nano-features using EBPG5150 (100 kV) for sub-100 nm features. Use eLINE Plus for CD-SEM verification of pattern dimensions.
# '''Develop and Inspect'''<br>Develop in ZED-N50 (ZEP) or MIBK:IPA (PMMA). Rinse and dry. Inspect pattern quality and critical dimensions using eLINE Plus CD-SEM or Filmtek for resist thickness confirmation.
# '''Etch or Metal Deposition'''<br>For nanochannels: RIE to transfer pattern into Si or SiO₂. For plasmonic nanostructures: e-beam evaporation of Au/Ti followed by lift-off. DRIE for deep features or through-wafer channels.
# '''Metrology — Verify Etch Depth and Feature Size'''<br>Measure etch depth with Dektak XT (contact profilometer) or OLS5500 confocal. Verify sidewall quality with AFM if needed.
# '''PDMS Integration and Bonding'''<br>Integrate patterned substrate with PDMS microfluidic channels. Plasma activate both surfaces and bond. Verify channel alignment and seal integrity.

{{Note|This workflow crosses three facilities — CMM (EBL), ANFF-Q (etch/deposition), and Long Pocket (PDMS). Make sure you have RIMS access at both CMM and ANFF-Q before starting.}}

==== Summary ====

{| class="wikitable"
|-
! Parameter !! Detail
|-
| '''Facilities''' || CMM (Hawken) — EBL · ANFF-Q (AIBN) — etch/dep. · Long Pocket — PDMS
|-
| '''Key instruments''' || Raith EBPG5150 (100 kV) · eLINE Plus (CD-SEM) · Oxford RIE · DRIE (ANFF-Q)
|}

----

=== Workflow 4 — Bio-Optomechanical Devices (Nanobeams, Membranes, Optical Traps) ===

''Suspended SiNx or Si nanobeams and membranes for optomechanical sensing of biological specimens. High-resolution EBL for nanoscale features, DRIE/XeF₂ for device release.''

'''Facility route:''' ANFF-Q → CMM → ANFF-Q → ANFF-Q → CMM

==== Steps ====

# '''SiNx or Si Device Layer Deposition'''<br>Deposit low-stress silicon nitride (SiNx) via ICP-CVD or LPCVD. Thickness defines mechanical properties (resonance frequency, Q-factor). For SOI devices, use commercial SOI wafers.
# '''EBL Patterning of Nanobeams / Membrane Features'''<br>Spin HSQ or ZEP on device layer. Expose nanoscale beam and hole patterns using EBPG5150 at 100 kV. Beam widths typically 100–500 nm; holes <200 nm for photonic crystal membranes.
# '''RIE Etch of Device Layer'''<br>Transfer EBL pattern into SiNx or Si device layer by RIE. Use SF₆/CHF₃ chemistry for SiNx. Vertical, anisotropic etch critical for well-defined device geometry.
# '''Device Release'''<br>Release suspended structures by selectively removing the sacrificial oxide layer. XeF₂ or vapour HF for isotropic SiO₂ undercut and release without stiction. Critical step — handle carefully to avoid collapse.
# '''Metrology — Verify Dimensions and Surface Quality'''<br>Image released structures with SEM to verify beam dimensions and undercut. Measure surface roughness via AFM. Use OLS5500 for non-contact topography of fragile released devices.

==== Summary ====

{| class="wikitable"
|-
! Parameter !! Detail
|-
| '''Facilities''' || CMM (Hawken) — EBL · ANFF-Q (AIBN) — dep./etch
|-
| '''Key instruments''' || Raith EBPG5150 (100 kV) · ICP-CVD (ANFF-Q) · XeF₂ etcher (ANFF-Q) · PRIMAXX vapour HF
|}

----

== Photonics — Si Photonics, Metalenses, Integrated Photonics ==

Nanofabrication workflows for integrated photonic devices. EBL at CMM is the primary patterning tool for sub-100 nm waveguides, gratings, and metasurface elements. RIE at ANFF-Q for pattern transfer.

=== Workflow 1 — Silicon Photonics: Waveguides, Ring Resonators, Grating Couplers ===

''EBL-defined silicon-on-insulator (SOI) waveguide devices. Critical dimensions typically 200–500 nm width. ZEP or HSQ as hard mask for high-quality sidewalls after ICP-RIE.''

'''Facility route:''' CMM → CMM → ANFF-Q → CMM → ANFF-Q

==== Steps ====

# '''Substrate Prep and Resist Coating'''<br>Clean SOI wafer in Diener plasma cleaner to remove organics. Spin ZEP520A (positive-tone etch mask) or HSQ 6% (negative-tone high-resolution hard mask). Bake on CEE Apogee hotplate.
# '''EBL Exposure — Waveguides and Grating Couplers'''<br>Expose waveguide layout at 100 kV on EBPG5150. Use proximity correction (BEAMER) for dense grating coupler regions. Typical dose: 160–200 µC/cm² for ZEP at 100 kV. Verify CD with eLINE Plus after develop.
# '''ICP / RIE Etch of Si Device Layer'''<br>Transfer waveguide pattern into Si device layer by ICP or RIE using HBr/Cl₂ or SF₆/C₄F₈ chemistry. Etch depth = Si layer thickness (typically 220 nm for standard SOI). Sidewall angle and roughness are critical for propagation loss.
# '''Metrology — SEM Inspection and Profilometry'''<br>Inspect waveguide cross-section in SEM to verify etch depth and sidewall angle. Measure step height with Dektak XT. Surface roughness via AFM — critical for propagation loss estimation.
# '''Optional: SiO₂ Cladding Deposition'''<br>Deposit upper SiO₂ cladding by ICP-CVD or sputtering to achieve symmetric waveguide mode and protect device. Index matching between core and cladding determines mode confinement.

{{Hint|Grating couplers and dense photonic crystal regions require BEAMER proximity correction. Factor this into your pattern file preparation time before the EBL session.}}

==== Summary ====

{| class="wikitable"
|-
! Parameter !! Detail
|-
| '''Facilities''' || CMM (Hawken) — EBL + metrology · ANFF-Q (AIBN) — etch/dep.
|-
| '''Key instruments''' || Raith EBPG5150 (100 kV) · eLINE Plus (CD-SEM) · Oxford RIE · ICP-CVD (ANFF-Q)
|-
| '''Typical resists''' || ZEP520A (positive, etch mask) · HSQ 6% (negative, hard mask) · PMMA (lift-off for metal contacts)
|}

----

=== Workflow 2 — Metalens and Metasurfaces: TiO₂, GaN, Si Nanopillars ===

''High-aspect-ratio dielectric nanopillars (TiO₂, GaN, or Si) patterned by EBL and etched for flat optics applications. Sub-100 nm pillar diameters with high aspect ratios require careful etch optimisation.''

'''Facility route:''' ANFF-Q → CMM → CMM → ANFF-Q → CMM

==== Steps ====

# '''Device Layer Deposition (TiO₂ / GaN / Si)'''<br>Deposit high-index dielectric layer by sputtering (TiO₂, SiNx) or CVD. Layer thickness defines pillar height and operating wavelength. ALD-deposited TiO₂ preferred for visible-wavelength metalenses.
# '''HSQ Hard Mask Exposure (EBPG5150)'''<br>Spin HSQ negative-tone resist directly on device layer. Expose pillar array at 100 kV — high dose (1,200–1,800 µC/cm²) required. HSQ acts as a hard mask with excellent etch selectivity. Dense pillar arrays benefit from proximity correction.
# '''Develop and CD-SEM Verification'''<br>Develop in TMAH 25%. HSQ crosslinks to SiO₂-like material — undeveloped HSQ dissolves. Image pillar pattern in eLINE Plus CD-SEM to verify diameter, pitch, and dose-related deviations before etching.
# '''High-Aspect-Ratio RIE Etch of Pillars'''<br>Etch device layer through HSQ mask using Cl₂/BCl₃ (TiO₂, GaN) or HBr/SF₆ (Si). Target aspect ratio 10:1 or greater. Sidewall passivation chemistry critical for vertical profiles. Contact ANFF-Q staff for chemistry advice.
# '''SEM / AFM Characterisation of Pillar Array'''<br>Image pillar array in SEM — tilt view to assess sidewall angle and height. FIB cross-section for precise aspect ratio measurement. AFM for surface roughness on pillar tops.

{{Warning|HSQ calibration on the EBPG5150 is currently marked as due for update. Run a dose array on your first metalens exposure before committing to a full chip.}}

==== Summary ====

{| class="wikitable"
|-
! Parameter !! Detail
|-
| '''Facilities''' || CMM (Hawken) — EBL + SEM · ANFF-Q (AIBN) — dep./etch
|-
| '''Key instruments''' || Raith EBPG5150 — HSQ exposure · eLINE Plus — CD-SEM · Sputtering system (ANFF-Q) · Oxford RIE (ANFF-Q)
|}

----

=== Workflow 3 — Plasmonic Nanostructures: Gold Nanoantennas, Bow-Ties, Nanogaps ===

''EBL lift-off of Au/Ti nanostructures for SERS, near-field enhancement, and optical antenna applications. Sub-50 nm gap features achievable at 100 kV.''

'''Facility route:''' CMM → CMM → ANFF-Q → CMM → ANFF-Q

==== Steps ====

# '''Bilayer PMMA Resist Coat'''<br>Spin PMMA A2 (lower layer) then A4 (upper layer) to create a controlled undercut profile. Bake between layers. Undercut ensures clean lift-off separation.
# '''EBL Exposure and Develop'''<br>Expose nanoantenna patterns at 100 kV. Dose ~350–400 µC/cm² for PMMA A4 on SiO₂. Develop in MIBK:IPA 1:3 for 60 s at 23 °C. Inspect gaps in eLINE CD-SEM before proceeding.
# '''Au / Ti E-Beam Evaporation'''<br>Deposit 2–5 nm Ti adhesion layer, then 20–50 nm Au by e-beam evaporation. Low deposition rate (<0.5 Å/s) for Au to minimise resist heating. Keep total metal thickness well below resist thickness for clean lift-off.
# '''Lift-Off in Acetone'''<br>Soak in acetone (or NMP for stubborn lift-off) to dissolve PMMA and remove metal from unwanted areas. Ultrasonication at low power assists lift-off without damaging structures. Rinse in IPA, dry.
# '''SEM Characterisation and Gap Verification'''<br>Image nanoantenna array in SEM. Verify gap dimensions and structure quality. Use WITec Raman-AFM-SNOM for optical near-field characterisation if needed.

==== Summary ====

{| class="wikitable"
|-
! Parameter !! Detail
|-
| '''Facilities''' || CMM (Hawken) — EBL · ANFF-Q (AIBN) — dep./SEM
|-
| '''Key instruments''' || Raith EBPG5150 · eLINE Plus (CD-SEM) · E-beam evaporation (ANFF-Q) · JEOL IT-300 SEM (ANFF-Q) · WITec Raman-AFM-SNOM
|}

----

== MEMS — Bulk and Surface Micromachining ==

Fabrication workflows for MEMS devices including cantilevers, membranes, accelerometers, and resonators. Relies on ANFF-Q DRIE for deep Si etching and XeF₂ / vapour HF for device release.

=== Workflow 1 — Si / SiNx Cantilevers and Mechanical Resonators ===

''Fabrication of free-standing cantilevers and doubly-clamped beams by top-down lithography and wet or dry release. Used for AFM probes, mass sensors, and optomechanical resonators.''

'''Facility route:''' ANFF-Q → CMM → ANFF-Q → ANFF-Q → CMM

==== Steps ====

# '''SiNx Device Layer Deposition'''<br>Deposit low-stress SiNx by LPCVD or ICP-CVD on Si/SiO₂ substrate. Stress control is critical — stoichiometry determines residual stress and resonance frequency of the final beam.
# '''EBL or Optical Lithography Patterning'''<br>For sub-micron beam widths use EBPG5150 with ZEP or HSQ. For beams >1 µm, ANFF-Q photolithography is sufficient and faster. Pattern defines beam outline and any integrated nanostructures (holes, tips).
# '''RIE Etch of SiNx Layer'''<br>Etch SiNx through resist mask using CHF₃/O₂ or SF₆/CHF₃ chemistry in RIE. Timed etch — stop on SiO₂ or Si substrate. Vertical sidewalls important for well-defined beam geometry.
# '''Sacrificial Layer Release (XeF₂ or Vapour HF)'''<br>Isotropically etch sacrificial oxide beneath SiNx beam to release free-standing structure. XeF₂ for Si undercut; vapour HF (PRIMAXX) for SiO₂ sacrificial layer. Both are dry-release processes — no stiction vs wet KOH.
# '''SEM and AFM Characterisation'''<br>Image released cantilever in SEM to verify geometry and suspension. Measure surface roughness and beam profile with AFM. Tilted SEM view confirms undercut and beam suspension.

==== Summary ====

{| class="wikitable"
|-
! Parameter !! Detail
|-
| '''Primary facility''' || ANFF-Q (AIBN)
|-
| '''Supporting''' || CMM (Hawken) — EBL (optional for sub-micron beams)
|-
| '''Key instruments''' || LPCVD furnace (ANFF-Q) · XeF₂ etcher (ANFF-Q) · PRIMAXX vapour HF · Oxford RIE (ANFF-Q)
|}

----

=== Workflow 2 — Bulk Si Micromachining: Deep Trenches, Through-Wafer Vias, Pressure Membranes ===

''DRIE Bosch process for high-aspect-ratio features in bulk silicon. Used for pressure sensors, inertial MEMS, and microfluidic master moulds.''

'''Facility route:''' ANFF-Q → ANFF-Q → ANFF-Q → CMM

==== Steps ====

# '''Hard Mask Deposition and Patterning'''<br>Deposit SiO₂ or SiNx hard mask by ICP-CVD. Pattern by photolithography (ANFF-Q) for features >1 µm or EBL (CMM) for sub-micron. Etch hard mask in RIE before DRIE.
# '''DRIE — Bosch Process'''<br>Alternating SF₆ etch / C₄F₈ passivation cycles to achieve vertical deep Si etching. Etch rate ~5–10 µm/min. Sidewall scalloping is characteristic — controllable by cycle parameters. Contact ANFF-Q staff for recipe advice.
# '''Hard Mask Strip and Dicing'''<br>Strip hard mask in BOE (SiO₂) or H₃PO₄ (SiNx). Dice wafer into individual dies using dicing saw. Clean dies in piranha or standard RCA clean.
# '''Metrology — Etch Depth and Profile'''<br>Measure etch depth with Dektak XT or OLS5500 (non-contact). FIB cross-section in SEM for sidewall profile assessment and scallop measurement.

==== Summary ====

{| class="wikitable"
|-
! Parameter !! Detail
|-
| '''Primary facility''' || ANFF-Q (AIBN)
|-
| '''Metrology''' || CMM (Hawken)
|-
| '''Key instruments''' || DRIE — Bosch process (ANFF-Q) · Dicing saw (ANFF-Q) · Dektak XT profilometer
|}

----

=== Workflow 3 — Surface Micromachining: Polysilicon over Sacrificial Oxide ===

''Classic surface MEMS process: poly-Si structural layer deposited over sacrificial SiO₂, patterned, then released by HF etching. Suitable for actuators, comb drives, and gyroscopes.''

'''Facility route:''' ANFF-Q → ANFF-Q → ANFF-Q → ANFF-Q → ANFF-Q

==== Steps ====

# '''Sacrificial Oxide Deposition'''<br>Grow or deposit SiO₂ sacrificial layer (thermal oxidation or ICP-CVD). Thickness determines the released gap between structural layer and substrate. Typically 0.5–2 µm.
# '''Poly-Si Structural Layer Deposition'''<br>Deposit doped polysilicon by LPCVD. Thickness = structural layer thickness (typically 1–5 µm). Anneal to reduce residual stress. Doping ensures electrical conductivity for electrostatic actuation.
# '''Pattern Poly-Si Structural Layer'''<br>Coat with photoresist (ANFF-Q photolithography suite) and pattern structural features — comb fingers, springs, anchor points. RIE etch poly-Si using SF₆ or HBr chemistry.
# '''Contact Metal Deposition and Patterning'''<br>Deposit Al or Au contact pads by e-beam evaporation and pattern by lift-off or wet etch. Contacts to anchored regions only — flying structures must remain free.
# '''Sacrificial Oxide Release (Vapour HF)'''<br>Selectively etch sacrificial SiO₂ using PRIMAXX vapour HF. Isotropic etch undercuts structural poly-Si to release moving parts. Dry release avoids stiction from surface tension. Etch time determines undercut extent — design release holes in structural layer accordingly.

{{Hint|Design etch-access holes in your structural poly-Si layer (typically 2–5 µm diameter, on a grid) to allow HF vapour to reach the sacrificial oxide underneath large structures.}}

==== Summary ====

{| class="wikitable"
|-
! Parameter !! Detail
|-
| '''Primary facility''' || ANFF-Q (AIBN) — all steps
|-
| '''Key instruments''' || LPCVD furnace (ANFF-Q) · PRIMAXX vapour HF · RIE (ANFF-Q) · E-beam evaporation (ANFF-Q)
|}

----

== Quantum Devices — Superconducting Qubits, Spin Qubits, NV Centres ==

High-resolution EBL at CMM combined with superconducting metal deposition at SMP. Multi-facility workflow requiring coordination between CMM (EBPG5150) and SMP (angle evaporation).

=== Workflow 1 — Transmon Qubit: Al/AlOx/Al Dolan Bridge Josephson Junctions ===

''The standard Al double-angle evaporation process for transmon qubits. PMMA bilayer EBL at CMM followed by Al angle evaporation at SMP to form the AlOx tunnel barrier junction.''

'''Facility route:''' CMM → CMM → CMM → SMP → SMP → CMM

==== Steps ====

# '''Substrate Clean and PMMA Bilayer Coat'''<br>Clean Si or sapphire substrate in Diener O₂/Ar plasma. Spin PMMA A2 (lower layer, softer — gives undercut) then PMMA A4 (upper layer, higher MW). Bake each layer on CEE Apogee hotplate. Bilayer essential for Dolan bridge geometry.
# '''EBPG5150 EBL — Qubit and Junction Pattern'''<br>Expose qubit geometry (capacitor pads, coupling lines) and Dolan bridge at 100 kV. Junction bridge typically 100–200 nm wide. Dose ~350–400 µC/cm² for PMMA A4. Use BEAMER proximity correction for the dense junction region.
# '''Develop and Inspect'''<br>Develop in MIBK:IPA 1:3 for 60–75 s at 23 °C. The bilayer creates a controlled undercut in the A2 layer. Inspect Dolan bridge dimensions in eLINE CD-SEM — bridge width and undercut are critical for junction area and Josephson energy.
# '''Double-Angle Al Evaporation at SMP'''<br>Transfer sample to SMP superconducting evaporator. Evaporate first Al layer at +angle (e.g. +17°), oxidise in controlled O₂/Ar to form AlOx tunnel barrier, then evaporate second Al layer at −angle. The two layers overlap only under the bridge — this is the Josephson junction.
# '''Lift-Off'''<br>Soak in acetone or NMP to dissolve PMMA and remove unwanted Al. Gentle ultrasonic agitation. Rinse in IPA. The junction and qubit geometry remain. Inspect in optical microscope before SEM.
# '''SEM Inspection and Metrology'''<br>Image junction in SEM to verify bridge geometry and overlap area. Junction normal resistance (Rn) measured electrically at room temperature to estimate Josephson energy. FIB cross-section if oxide layer characterisation needed.

{{Note|This workflow requires RIMS accounts at CMM and access arranged with the SMP group. Confirm SMP evaporator availability before scheduling your EBL session — the sample should go from develop to evaporation within a few hours to avoid resist degradation.}}

==== Summary ====

{| class="wikitable"
|-
! Parameter !! Detail
|-
| '''Facilities''' || CMM (Hawken) — EBL · SMP (Parnell) — Al evaporation
|-
| '''Key instruments''' || Raith EBPG5150 (100 kV) · eLINE Plus (CD-SEM) · SMP superconducting evaporator
|-
| '''Critical parameters''' || Bridge width: 100–200 nm · Al₁: ~30 nm · Oxidation: O₂/Ar 1–10 min · Al₂: ~60 nm · Target Rn: 5–15 kΩ
|}

----

=== Workflow 2 — Nb / NbTiN Microwave Resonators and Feedlines ===

''Coplanar waveguide resonators and transmission lines in Nb or NbTiN for qubit readout circuits. EBL-defined at CMM, Nb deposited at SMP.''

'''Facility route:''' SMP → CMM → ANFF-Q → CMM

==== Steps ====

# '''Nb or NbTiN Film Deposition at SMP'''<br>Deposit Nb or NbTiN on Si or sapphire substrate at SMP. Film thickness = device layer thickness (typically 50–200 nm). Film quality (Tc, residual resistance) critical for resonator Q-factor.
# '''EBL Patterning of Resonator Geometry'''<br>Coat with ZEP520A. Expose CPW resonator pattern (50 Ω gaps typically 4–10 µm) plus any sub-micron features at 100 kV on EBPG5150. Develop in ZED-N50.
# '''Nb RIE Etch'''<br>Transfer pattern into Nb film by RIE using SF₆/Ar or CF₄/O₂ chemistry. Timed etch — stop on Si/sapphire substrate. Nb is a hard material — expect lower etch rates than Si.
# '''SEM Inspection'''<br>Verify CPW gap dimensions and feature quality in SEM. Measure Nb film thickness via Dektak XT step height on a test area.

==== Summary ====

{| class="wikitable"
|-
! Parameter !! Detail
|-
| '''Facilities''' || SMP (Parnell) — Nb dep. · CMM (Hawken) — EBL · ANFF-Q (AIBN) — etch
|-
| '''Key instruments''' || SMP superconducting evaporator · Raith EBPG5150 (100 kV) · Oxford RIE (ANFF-Q)
|}

----

== Organic Electronics — OLEDs, OPVs, Perovskite Devices ==

Fabrication workflows for organic light-emitting devices, organic photovoltaics, and perovskite solar cells. Primarily the COPE cleanroom at SCMB with supporting characterisation at ANFF-Q.

=== Workflow 1 — Small-Molecule OLED: ITO / HTL / EML / ETL / Al Cathode ===

''Standard vacuum-deposited small-molecule OLED stack. All organic layers deposited by thermal evaporation in COPE cleanroom. ITO anode patterned by photolithography at ANFF-Q.''

'''Facility route:''' ANFF-Q → COPE → COPE → ANFF-Q

==== Steps ====

# '''ITO Anode Deposition and Patterning'''<br>Deposit ITO by sputtering at ANFF-Q. Pattern anode geometry by photolithography and wet etch. Clean ITO surface thoroughly — O₂ plasma treatment (ANFF-Q Tergeo cleaner) before organic deposition to improve wettability and hole injection.
# '''Organic Layer Deposition (COPE Evaporator)'''<br>Sequentially deposit HTL (e.g. NPB), EML (host:guest system), ETL (e.g. Alq3), and LiF electron injection layer by thermal evaporation in COPE cleanroom under high vacuum. Each layer deposited through shadow masks.
# '''Al Cathode Deposition and Device Testing'''<br>Deposit Al cathode through shadow mask without breaking vacuum. Test device J-V characteristics, luminance, and EL spectra using in-cleanroom probe station at COPE.
# '''Optical and Electrical Characterisation'''<br>Full device characterisation at ANFF-Q: EL spectrum, CIE coordinates, efficiency (cd/A, lm/W). Solar simulator for OLED degradation studies. Confocal microscopy for emission uniformity.

{{Note|COPE cleanroom is primarily internal. Contact the COPE group via SCMB for collaborative access to this workflow.}}

==== Summary ====

{| class="wikitable"
|-
! Parameter !! Detail
|-
| '''Primary facility''' || COPE (SCMB)
|-
| '''Supporting''' || ANFF-Q (AIBN) — ITO / characterisation
|-
| '''Key instruments''' || COPE organic thermal evaporator · Sputtering system (ANFF-Q) · Tergeo plasma cleaner (ANFF-Q) · Semiconductor analyser (ANFF-Q)
|}

----

=== Workflow 2 — Perovskite Solar Cell: n-i-p Planar Architecture ===

''Solution-processed perovskite absorber with TiO₂ electron transport layer and spiro-OMeTAD hole transport layer. Spin coating at COPE cleanroom.''

'''Facility route:''' ANFF-Q → COPE → COPE → ANFF-Q

==== Steps ====

# '''ITO Substrate Preparation'''<br>Clean ITO-coated glass by sequential sonication in acetone, IPA, and deionised water. O₂ plasma clean (ANFF-Q Tergeo) immediately before deposition to improve surface energy.
# '''ETL and Perovskite Spin Coating'''<br>Spin coat compact TiO₂ ETL (titanium isopropoxide in ethanol), anneal at 500 °C. Spin coat perovskite precursor solution (MAPbI₃ or mixed-halide) in glovebox or controlled atmosphere. Anti-solvent drip during spinning. Anneal at 100 °C.
# '''HTL and Au Contact Deposition'''<br>Spin coat spiro-OMeTAD HTL. Evaporate Au back contact in COPE evaporator through shadow mask. Encapsulate device to prevent moisture degradation.
# '''J-V and IPCE Characterisation'''<br>Measure PCE, Voc, Jsc, FF using Class AAA solar simulator. Measure IPCE/EQE spectrum. Stability testing under continuous illumination.

==== Summary ====

{| class="wikitable"
|-
! Parameter !! Detail
|-
| '''Primary facility''' || COPE (SCMB)
|-
| '''Supporting''' || ANFF-Q (AIBN) — characterisation
|-
| '''Key instruments''' || COPE spin coater (glovebox) · COPE evaporator · Class AAA solar simulator (ANFF-Q) · QE/IPCE/IV system (ANFF-Q) · Tergeo plasma cleaner (ANFF-Q)
|}

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